Epidemiological and molecular characterization of Enterobius vermicularis cases in Mersin, Turkey: An analysis based on mitochondrial DNA cox1 gene sequences

Abstract

Enterobius vermicularis is among the most common intestinal helminths, especially in children. Mitochondrial cox1 gene analyses revealed three genotypes (A, B, C). We aimed to evaluate the epidemiological characteristics and cox1 genotypes of E. vermicularis cases diagnosed at Mersin University Hospital. Between January 2017 and December 2023, 1496 samples were examined using the cellophane tape method, and 75 positives were identified. Epidemiological data were retrospectively analyzed. DNA was isolated from 30 positive samples via the phenol–chloroform method, and nested PCR products of the cox1 gene were sequenced. Phylogenetic analyses were performed using GenBank sequences. In a sample of patients with gastrointestinal signs, the positivity rate for E. vermicularis was 5 % (75/1496). Among the positive cases, 93.3 % were pediatric, with a mean age of 8.7 ± 7.7 years, and the highest prevalence (9 %) was observed in the 5–10 age group. The most commonly reported symptoms included abdominal pain (49.3 %), perianal itching (40 %), and nocturnal drooling (33.3 %). Molecular analysis revealed that all isolates belonged to genotype B, and eight haplotypes were identified. Six haplotypes were novel, while two haplotypes were identical to sequences previously reported from Iran, Iraq, and Greece. Although the prevalence of E. vermicularis in our region was relatively low, it remains a significant public health concern, especially among school-aged children. Genotype B, widely reported in Europe and the Middle East, was dominant in our study population. Moreover, haplotypes in this study were identical or closely related to those from neighboring countries. Further studies from different regions of Turkey are needed for a more comprehensive epidemiological assessment.